Sealing elements having a rigid supporting component and an elastomer part arranged thereon are known in principle. In conjunction with valve elements, there is the problem that the point in time at which a valve opens and closes is not defined precisely since that part of the valve which, by virtue of displacement, causes the valve to be opened and closed is pushed into the elastomer material of the sealing element to a more or less pronounced extent, depending on the fluid pressure acting on it, as a result of which the point in time at which the valve opens and closes varies. This is undesirable in a large number of applications since the valve is intended to have constant, precisely defined opening and closing behavior.
U.S. Pat. No. 3,282,594 discloses a sealing element according to the preamble of claim 1. A similar sealing element is known from GB 2 256 687 A. The factor which is common to both sealing elements is that the elastomer constituent of the sealing element is injection molded in one piece with the rigid supporting body. This is intended to ensure good sealing between the elastomer material and the material of the rigid supporting body.